THE SIR SUPPLIED DR. HO WITH 5G OF L-[1-13C] TYROSINE. IN OUR LABORATORY, WE ARE APPLYING MULTINUCLEAR AND MULTIDIMENSIONAL NMR AND MOLECULAR BIOLOGICAL TECHNIQUES TO ELUCIDATE THE STRUCTURES, DYNAMICS, AND INTERACTIONS OF PROTEINS IN SOLUTION AND IN SOLID. FROM OUR RESEARCH, WE HOPE TO GAIN A BETTER UNDERSTANDING OF THE STRUCTURE-FUNCTION RELATIONSHIPS IN PROTEINS. THERE ARE THREE PROTEINS THAT ARE BEING STUDIED IN OUR LABORATORY. FIRST, WE ARE USING MULTIMOLECULAR AND MULTIDIMENSIONAL SOLUTION AND SOLID STATE NMR TECHNIQUES TO INVESTIGATE THE STRUCTURE AND DYNAMICS OF GLUTAMINE-BINDING PROTEIN OF ESCHERICHIA COLI, A PROTEIN OF 25,000 DALTONS. SECOND, WE ARE USING SOLUTION AND SOLID-STATE NMR TECHNIQUES TO INVESTIGATE THE STRUCTURE AND DYNAMICS OF D-LACTATE DEHYDROGENASE OF ESCHERICHIA COLI, A MEMBRANE-ASSOCIATED PROTEIN OF 65,000 DALTONS. THIRD, WE HAVE CONSTRUCTED A PLASMID (PHE2) TO EXPRESS UNMODIFIED HUMAN NORMAL ADULT HEMOGLOBIN IN ESCHERICHIA COLI. USING OUR HEMOGLOBIN EXPRESSION SYSTEM IN ESCHERICHIA COLI, WE PLAN TO PREPARE 13C-,15N-, AND 2H-LABELED HEMOGLOBIN. IN COLLABORATION WITH DR. A. BAX OF THE NATIONAL INSTITUTES OF HEALTH, WE PLAN TO CARRY OUT AN NMR PROJECT TO APPLY MODERN MULTINUCLEAR AND MULTIDIMENSIONAL NMR METHODOLOGY TO ASSIGN THE POLYPEPTIDE BACKBONE RESONANCES OF HEMOGLOBIN, A PROTEIN OF 65,000 DALTONS.